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– Sklivvz♦Apr 30 '16 at 20:16

4

Also -- some of the comments were borderline racist. Posting racist flamebait will get your account suspended very quickly.
– Sklivvz♦Apr 30 '16 at 20:17

4

The US is a strange place. Who is black? The US seems to call anybody "black" who has just one ancestor who was African. They may also have 1, 3, 7, or 15 ancestors who were light-skinned, but still they count as "black". The statistics should take into account the fraction of "blackness" to have any meaning.
– RedSonjaMay 4 '16 at 7:49

3

@RedSonja That was true at one time. Now federal government considers white as "A person having origins in any of the original peoples of Europe, the Middle East, or North Africa", and permits people to state they are two or more races. See the last page of the following ATF document for example: atf.gov/resource-center/docs/non-immigrant-alienspdf/download
– DavePhDMay 5 '16 at 14:00

One must bear in mind that crimes are prejudicially "hung" on racial minorities. See Miami Herald article from July 12, 2018: “If they have burglaries that are open cases that are not solved yet, if you see anybody black walking through our streets and they have somewhat of a record, arrest them so we can pin them for all the burglaries,” one cop, Anthony De La Torre, said in an internal probe ordered in 2014. “They were basically doing this to have a 100% clearance rate for the city."
– Daniel R HicksJul 12 '18 at 21:02

The report makes the following statement about potential bias due to unknown information:

While many agencies report supplemental data on
homicides, much of the data concerning offenders may
not be reported because no suspects were identified or
the agency chose not to report the information. The most
significant problem in using SHR data to analyze offender
characteristics is the sizable and growing number
of homicides in the data file for which no offender
information is reported. Ignoring these homicides with
no offender information would understate calculated
rates of offending by particular subgroups of the
population, distort trends over time among these same
subgroups, and bias observed patterns of offending to the
extent that the rate of missing offender data is associated
with offender characteristics.

To adjust for homicides with no offender information,
a method for offender imputation was devised that uses
available information about murder victims for which
corresponding offender information was provided as well
as those with missing offender information. Through this
imputation algorithm, the demographic characteristics
of unidentified offenders were inferred on the basis of
similar homicide cases—similar in terms of the victim’s
demographic profile, circumstances of the homicide such
as felony or argument, location of the homicide (region
and urban), gun involvement, and year of the offense—
for which offender data were provided. In other words,
unknown offender profiles were estimated based on the
offender profiles in offender-known cases, matched on
victim age, sex, and race; circumstances of the homicide;
location of the homicide; gun involvement; and year.
Offender-based estimates in this report were imputed
using this procedure. Other estimates in this report
were based on homicides with known attributes, unless
otherwise indicated.
An estimated 30.8% of homicides involved an unknown
number of offenders. For these homicides, the offender
imputation method conservatively assumed the number
of offenders to be one, likely resulting in an undercount
of the number of homicides involving multiple offenders.

All rates were calculated using the estimated number
of homicide victims or offenders as the numerator and
dividing by the U.S. resident population estimates for
the appropriate groups or subgroups. This report used
bridged-race population estimates developed by the
National Center for Health Statistics and the U.S. Census
Bureau.

The report also finds that people are overwhelmingly being killed by members of their own race:

84% of white victims were killed by whites
93% of black victims were killed by blacks

Your math is skewed - 5,375 out of 14,132 is 38% - Omitting the unknowns would only be valid if you had strong evidence that the Unknowns would be distributed about the same...
– DanielJul 12 '18 at 13:07

@Daniel Yes, I agree. Only the information above the horizontal line considers distribution of unknowns.
– DavePhDJul 12 '18 at 13:28

Through this imputation algorithm, the demographic characteristics of unidentified offenders were inferred on the basis of similar homicide cases Given that murder statistics in the US are quite vague, this statement does not give me any confidence in those numbers at all (even through they are probably the best you can get)
– David MJul 13 '18 at 4:33

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